Apple drops Safari Technology Preview 47 with new APIs, Spectre fixes

A new version of Apple's experimental Safari branch was made available to web professionals late Wednesday, bringing a number of API enhancements and folding in patches for the Spectre vulnerability.

Aside from the Spectre mitigations - which match those rolled out to iOS and High Sierra in recent days - the headline feature from the latest Safari Technology Preview is a new experimental storage access API. The API would allow specific third-party cookies to be accessed when requested by the user.

This proposal is designed to help third-party services embedded on a website - the WebKit team holds up commenting widgets and video services as prime examples - read and write their own cookies in multiple contexts.

WebKit would only allow this following a user interaction, like a tap or a click, to avoid surreptitious tracking without the user's knowledge. It would also respect locally-set rules including whitelists and blacklists.

Other changes include wide-ranging improvements to service workers, which allow websites to run processes in the background without the need for user interaction. Enhancements to picture-in-picture, Web Inspector, and the Clipboard API are also included.

Safari Technology Preview 47 is available now for download from Apple's developer website.